Due to the development of communications systems, consumers, such as companies and individuals, commonly use various types of wireless terminals. Current mobile communications systems belonging to a 3rd generation project partnership (3GPP) family, such as long-term evolution (LTE) and LTE-Advanced, are high-speed, high capacity communications systems grown out of voice-centric services. These systems can transmit and receive various types of data, such as video data or wireless data. Thus, it is necessary to develop technologies to wirelessly transmit a large amount of data at a high transmit rate similar to those of wired communications networks. Deployments, such as a plurality of cells or a plurality of small cells, have been introduced. Accordingly, it is required to develop a technology and a method for applying carrier aggregation (CA) in a variety of deployment scenarios. In addition, it is also required to develop a technology for supporting joint operations and CA, which perform signal transmission and reception among a plurality of base stations or in a heterogeneous network when two more cells are established in different duplex modes, such as time division duplex (TDD) and frequency division duplex (FDD). For example, the efficiency of an entire network may be affected by the manner of establishing downlink HARQ-ACK timing in a joint operation in which a primary cell (Pcell) and a secondary cell (Scell) have different duplex modes.